Methods for recycling metals from the nuclear industry

Abstract

Methods for processing metal components from the nuclear industry are described. In some embodiments, a method includes processing a component having a surface contaminated with radionuclides by dissolving at least a portion of the surface with an acid solution to produce a waste solution including the radionuclides, and separating the radionuclides from the waste solution. In some embodiments, a method includes processing a component including a target radionuclide by immersing at least a portion of the component in an electrolyte bath, applying an electric current to cause electrodissolution, and electroplating the target radionuclide from the solution onto a cathode. In some embodiments, a method includes processing a metal composite component by dissolving it to produce a solution including dissolved metal and particulate material, and separating the particulate material.

What is claimed is: 
     
         1 . A method of processing a metal component from the nuclear industry having a surface contaminated with radionuclides, the method comprising:
 dissolving at least a portion of the surface of the metal component with an acid solution to produce a contaminated solution including the radionuclides; and   selectively separating individual radionuclides from the radionuclides in the contaminated solution.   
     
     
         2 . The method of  claim 1  wherein the metal component comprises metal tubing and the dissolving comprises circulating the acid solution through an interior of the metal tubing. 
     
     
         3 . The method of  claim 1  comprising dissolving at least the portion of the surface of the metal component with a series of at least two different acid solutions. 
     
     
         4 . The method of  claim 1  wherein the acid solution comprises a mineral acid. 
     
     
         5 . The method of  claim 1  wherein the acid solution comprises an organic acid. 
     
     
         6 . The method of  claim 1  wherein selectively separating the individual radionuclides from the contaminated solution comprises separating the individual radionuclides via ion exchange media, selective precipitation, solvent extraction, and/or a carbon bed. 
     
     
         7 . The method of  claim 1  wherein the metal component is part of a steam generator. 
     
     
         8 . The method of  claim 1  wherein the acid solution comprises a mineral acid and an oxidizing agent. 
     
     
         9 . The method of  claim 8  wherein the mineral acid is hydrochloric acid. 
     
     
         10 . The method of  claim 8  wherein the oxidizing agent comprises hydrogen peroxide, permanganic acid, and/or a permanganate salt. 
     
     
         11 . The method of  claim 10  wherein the oxidizing agent is hydrogen peroxide. 
     
     
         12 . A method of processing a metal component from the nuclear industry comprising:
 immersing at least a portion of the metal component in an electrolyte bath, the portion of the metal component comprising radionuclides including a target radionuclide;   applying an electric current to the metal component to cause electrodissolution of the portion of the metal component in a solution, the solution including dissolved radionuclides from the radionuclides from the metal component; and   selectively electroplating the target radionuclide from the solution onto a cathode separately from other dissolved radionuclides from the metal component.   
     
     
         13 . The method of  claim 12  wherein the metal component is from a reactor vessel and/or an activated internal component of the reactor vessel. 
     
     
         14 . The method of  claim 12  wherein the portion of the metal component is a bulk-activated region of the metal component. 
     
     
         15 . The method of  claim 12  wherein the target radionuclide is a neutron activation product. 
     
     
         16 . The method of  claim 12  wherein the target radionuclide comprises Cobalt-60 and/or Nickel-63. 
     
     
         17 . The method of  claim 12  comprising recovering the target radionuclide from the cathode.